自适应流通机匣处理改善压气机性能的机理

Flow mechanisms of improving compressor performance through self recirculation casing treatment

关键词:  自适应流通  机匣处理  轴流压气机  失速  流动分布

Key words:  Self recirculation  Casing treatment  Axial Compressor  Stall  Flow distribution

摘要:

为了探索自适应流通机匣处理形式影响跨声压气机性能及流场的流动机理,文中采用非定常数值模拟方法研究了自适应流通机匣处理对NASA轴流Rotor37气动性能的影响。数值计算结果表明:自适应流通机匣处理能有效地延迟失速并在大部分流量范围内略微提高压气机的效率。通过详细的流场分析表明,该机匣处理能有效地增大叶顶区的气流进气角度,抑制了间隙泄漏涡在叶顶通道内的发展,同时阻止泄漏涡涡核在通过激波后破碎,提高了转子顶部通道的流通能力,进而减少叶顶区的流动损失。

Abstract:

Self recirculation casing treatment is known as an effective method to improve axial compressor performance and flow field.It is implemented by combining injection and bleed on the compressor shroud and has the characteristic of injecting or bleeding quantity self adjusting with the compressor work point varying.Effect of self recirculation casing treatment on the performance and flow field of NASA axial Rotor37 is performed with unsteady numerical method to explore the mechanism of self recirculation casing treatment affecting the performance and flow field of transonic compressor.The numerical results show that self recirculation casing treatment not only can suspend the stall effectively but also improve the compressor efficiency appreciably in the range of flow rate studied.The detailed analysis of the flow field at the blade tip shows that the magnitudes of flow inlet angle is increased and the development of tip leakage vortex is restrained with self recirculation casing treatment,which can prevent he breakdown of the clearance leakage vortex and improve effectively the current ability of blade tip passage.As the result,the loss of rotor tip area is receded.